Electrosurgical devices may be used in many surgical operations. Electrosurgical devices may apply electrical energy to tissue in order to treat tissue. An electrosurgical device may comprise an instrument having a distally mounted end effector comprising one or more electrodes. The end effector can be positioned against tissue such that electrical current may be introduced into the tissue. Electrosurgical devices can be configured for monopolar or bipolar operation. During monopolar operation, current may be introduced into the tissue by an active (or source) electrode on the end effector and returned through a return electrode. The return electrode may be a grounding pad and separately located on a patient's body. During bipolar operation, current may be introduced into and returned from the tissue by the active and return electrodes, respectively, of the end effector.
The end effector may include two or more jaws. At least one of the jaws may have at least one electrode. At least one jaw may be moveable from a position spaced apart from the opposing jaw for receiving tissues to a position in which the space between the jaws is less than that of the first position. This movement of the moveable jaw may compress the tissue held between. Heat generated by the current flow through the tissue in combination with the compression achieved by the jaw's movement may form hemostatic seals within the tissue and/or between tissues and, thus, may be particularly useful for sealing blood vessels, for example. The end effector may comprise a cutting member. The cutting member may be movable relative to the tissue and the electrodes to transect the tissue.
Electrosurgical devices also may include mechanisms to clamp tissue together, such as a stapling device, and/or mechanisms to sever tissue, such as a tissue knife. An electrosurgical device may include a shaft for placing the end effector proximate to tissue undergoing treatment. The shaft may be straight or curved, bendable or non-bendable. In an electrosurgical device including a straight and bendable shaft, the shaft may have one or more articulation joints to permit controlled bending of the shaft. Such joints may permit a user of the electrosurgical device to place the end effector in contact with tissue at an angle to the shaft when the tissue being treated is not readily accessible using an electrosurgical device having a straight, non-bending shaft.